I see no evidence in the post that they are thinking about implementing broader ways of monetising their traffic. There were wonderful suggestions --in HN and reddit proper-- in response to their first plea for help. Are they going to ignore other recommended approaches (e.g maintaining a proper ad inventory, sponsored sub reddits, employing a dedicated biz dev team, and so on) and assume that pledge drives will scale into the future?
They didn't explicitly say anything on the blog post because they don't have power to higher anyone without getting permission from above, they can't even get new servers without getting permission first. The best way to know what going on is to follow the developers/admins comments who are very much involved within the discussion: